Driving and stopping mechanism.



M. T. DENNE. DRIVING AND STOPPING MECHANISM.

APPLICATION FILED SEPT. 22. 1914.

1,272,016. V Patenfed July 9,1918.

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M. T. DENNE.

DRIVING AND STOPPING MECHANISM.

APPLICATION FILE D SEPT-22, I914- 1 ,272,01 6. Patenfied July 9, 1918.

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X. 773 m MarK Thomas Denne,

Yfd Mai W MARK THOMAS DENNE, OF RUSHDEN, ENGLAND.

DRIVING AND STOPPING MECHANISM.

Specification of Letters Patent.

7 Patented July 9, 1918.

Application filed September 22, 1914. Serial No. 863,023.

To all whom it may concern:

Be it known that I, MARK Trioivrns DENNE, a subject of the King of Great Brltain and Ireland, residing at Rushden, Northamptonshire, England, have invented new and useful Improvements in and Re lating to Driving and Stopping Mechanism, of which the following is a specification. V

This-invention has reference to improvements in and relating to driving and stopping mechanism principally intended for use with high speed machinesfor example boot and shoe machinery in which it is required that the machine can be started almost instantly at full speed and may thereafter be either slowed down gradually or stopped practically instantly, the practically instantaneous starting being brought about by the partial depression of a treadle or the like, the slowing down by a further moreor less gradualedepression vof the treadle, and the practically instantaneous stopping by releasingthe treadle after its partial depression.

In such machines the cam cylinder (or the like) has to be brought to a stop at a particular point in the path of its rotation to enable work to be inserted or removed and it has been customary to allow the cylinder to rotate beyond such point (when the treadle has been released) against a spring or air cushion or the like which spring or air cushion has brought the cylinder back to the desired point, generally against a stop.

My inventionconsists in a driving and stopping mechanism for use in particular with high speed machines and it comprises means operated for example by a treadle whereby (1) on the depression of the treadle the cam shaft or equivalent is caused to be rotated, (2) on the release of said treadle the cam shaft or equivalent is caused to stop, and (3) on the treadle being again depressed the cam shaft or equivalent is revolved in the reverse direction and then brought to a stop at a particular point in the path of its rotation. v

I have illustrated in the accompanying drawing by way of example an embodiment of my invention in which:

Figure l is a plan view partly in section of my improved stopping mechanism, the parts being shown in full driving position,

Fig. 2 is an end elevation, partly in section, on the line B, B (Fig. 1) and I Fig. 3 is a front View of a suitable switch mechanism to be hereinafter referred to.

Fig. 4 is a section on the line 4-4, Fig. 3.

Referring to the drawings, 1 is a cam (01' crank) shaft jou'rnaled in bearings 1 (only one of which is shown) of a machine to which the driving and stopping mechanism is applied. Mounted on said shaft is a sleeve 2 adapted to slide longitudinally thereon, and to rotate therewith by the engagement of a dog 3 which is keyed on said shaft and engages between projections on the inner periphery of a brake drum A: secured on said sleeve.

011 said brake drum 4 I mount a double coned friction member a one face of which may be made to frictionally engage a driving'pulley 5, loosely mounted on the shaft, and the other face of said member may be made to engage a brake member 6.

The sleeve 2 is acted on by springs 7 (only one of which is shown) which tend to move it ina direction to cause the friction cone to engage the pulley. The sleeve is formed with two flanges 8, 9 the former of which is of cam formation and provided with a swell 10.

J ournaled in the brake member 6 is a stud 11 the inner end of which is formed eccentrically and carries a cam roller 12. The outer end of said stud carries a dog or the like 13 the rocking of whichin the direction opposite to that in which a spring 14, surrounding said stud, tends to turn itwill cause, through the eccentricity of thestud, the roller 12 to be brought close to the flange 8, so that as the swell 10 contacts with the roller -(when the machine is in motion) the sleeve will be moved against the action of its springs 7 to thereby practically instantly withdraw the friction cone 4 from the driving pulley and put it into full frictional engagement with the brake member 6. This rocking of the dog 13 or equivalent against the action of its spring 14; is brought about by the operator depressing the ordinary starting lever or treadle as will be explained hereinafter.

If the brake member 6 was a fixture this engagement would almost instantly stop the machine, but it is well known that it is not 7 advisable to bring about such a sudden arv y'ond say the one eighth revolution or thereabout referred to I pivotally mount on the brakemeinber afro'd 15 adapted t'o sli'd'e in a Way or passage 15 which rod on the partial rotation of the brake member is brought into contact with a p'ositio'nstop 16 (which may be adjusted by a bolt 1t and also provided with a non-metallic contact face) which stops the further rotation of the brake member. V

In order to bring the brake member 6 and with it the cam shaft 1 and cylinder back to the actual desired or required stopping point I provide means to be actuated by the operator.

For example, I may form the rod carried by the brake 'liiemb'er with a notch 17 and engage one end of a pivotally mounted rocking lever 18 therein. The opposite end of said lever I form with a toothed segment 19 which is in gear with a toothed rack 20 which will be in a raised position when the rod referred to is in contact with the stop. To lower said rack, I provide a connection between it and a treadle so that upon depression 'of the treadle the rack will be lowered. In the illustrated embodiment of my invention, a connection is provided by which this rack is lowered by a second depression of the starting treadle. When the starting treadle is first depressed, the machine will be started as above described. Then the starting treadle has been released to a certain extent, the friction driving clutch is disengaged and the brake member put into frictional engagement permitting the parts to rotate vthe further o'ne eighth of a revolution or thereabout as already explained. The further and complete release of the starting treadle then operates a switch mechanism whereby the said treadle is connected up with the rack bar so that by then again depressing the same treadle the operator will return the cam cylinder and parts into the desired positions. I Asuitable switch mechanism consists in the following: i

A startingtreadle rod 21 at its upper end enters a recess or aperture in a bar 22 slidably mounted adjacent 'tothe rack bar 20 referred to and between the treadle rod and said bar 22 is a spring 23 which tends to normally maintain the bar in its raised position against a stop 23 Pivoted at its center on the said bar 22 is a disk 24 having a slot 24 across it centrally and angular to the horizontal when the machine is in operation with which slotat its, for the time being, lower end, one end of a link 25 is in engagement, the other end of said link being pivotally connected to a collar 21 fixedly mounted on the treadle rod 21. On the other side of said bar 22 to that at which the rack bar 20 is located is a second sliding bar 22 which latter has a slot with which a backwardly rojecting-f ridge or rim 24 on the disk 24 is adapted to engage at 24 when said disk is rocked in one direction; and the rack bar 20 is cut away to form a notch or shoulder '20 w'ithwhich said ridge or rim 24 may engage when the disk is tilted in the opposite direction. 7

The arrangement of the parts lastly described is such that'when the treadle is depressed and the machine is running, the disk 24 is so tilted that its rim portion 24 engages the slot in the bar 22 and it together with the bar 22 will have been pulled'd'ow n" against the action 'of the spring 23.' VVl'1en next the trea'dle is raised the two bars '22, 22 will ascend and the bar22 will operate means (to be described) to rock the dog 13 whereby the machine is stopped. On the treadle being further released the disk '24 will be rotated or rocked until its rim portion24 is disengaged from the bar 22? and is brought o posite the slot in the rack: bar 20 and the slot 24* in the disk will now have been swung so that theend with which the link 25 is engaged and which 'was the lower end of the slot is now the higher end- The spring referred to is sufliciently strong thatwhen next the 'treadl'e is depressed the link 25, instead of pulling down the bar 22 will travel down the slotuntil it-engages the oppo'site and lower end thereof. Further depression of the treadle will'first rock the disk 24 and cause its rim portion 24 to engage the slot in the rack bar 20 and thereafter the said rack bar and the bar 22 will descend with the tre'adle rod, the rack bar and parts 18, 15, operated by it serving to return the cam cylinder and the brake mem' her 6 to the actual desiredstopping point. The release of the treadle will raise the parts to their highest position with the exception of the'rack bar which will remain in its lowest position.

WVhen n'extfth'e 'treadle is depresscd the link 25 will first travel down the slot in the disk; then rock the disk 24 to cause its rim portion 24 to again engage the bar 22 and thereafter the parts will be depressed to thereby start the machine.

In order to rock the dog 13 t0 start the machine I provide a disk 26 rotatably mounted on a stud 27 said disk is formed with a notch or cut away portion 26 into stead of connecting the treadle rod directly to the disk.

The disk which actuates the dog may have a rod or link 29 connected to it whose opposite end operates a lever which controls one of thetensioning disks or the tension screw of a thread tensioning device the arrangement being such that when the treadle is released and the machine brought to a stop, the tension on the thread will be removed or released.

As has already been stated, the depression of the treadle to a certain partial eXtent causes the machine to be driven at its highest speed. In order to reduce the speed of the machine and even bring it to a stop (and in this case the machine is not necessarily brought to a stop at any particular position of its cam cylinder) I provide the stud 27 which is near to the beforementioned flange 9 or equivalent with an eccentric part carrying a roller 30 and mount the stud 27 so that it rotates with the disk 26 thereby causing the roller to be brought against the said'fiange 9, on the further depression of the treadle, and to more or less move thesleeve 2 and with it the double cone member 4 out of engagement with the driving pulley 5, a slight movement serving merely to decrease the speed of the machine whereas a full depression of the treadle will take the cone completely out of engagement with the driving pulley (without bringing the friction cone member into engagement with the brake member) and thus permit the machine to come to rest. When the treadle is held so depressed the operator can freely turn the cam cylinder by hand (a hand wheel, not shown, being perferably provided for this purpose) to enable him to make any necessary ad ustments.

The return movement of the brake member and other parts by the raising of the treadle, may be utilized by means of suitable mechanism to effect the releasing of the loop from the needle of a boot sewing ma chine or for any other purpose.

What I claim as my invention and desire to secure by Letters Patent is 1. In a driving and stopping mechanism for use in connection with high speed machines, the combination with a shaft, of a driving element, a treadle-operated connection, means to cause the shaft to be clutched to the driving element upon movement of.

said connection in one direction, means to unclutch said shaft from said driving element and bring said shaft to rest upon movement of said connection in an opposite direction, and means to reverse the direction of rotation of the shaft and bring it to rest in a predetermined position on a second movement of said connection in the firstnamed direction.

2. In a driving and stopping mechanism for use in connection with high speed machines, the combination with a shaft, of a driving pulley loose thereon, a treadleoperated connection, automatically-operative means to clutch said driving pulley to the shaft when said connection is moved downwardly, means to unclutch said shaft from the driving pulley and bring the shaft to rest upon upward movement of said connection, and means actuated by a second downward movement of said connection to reverse the direction of rotation of the shaft and to bring it to rest in a predetermined position.

3. In a driving and stopping mechanism, the combination with a shaft, of a driving pulley loose thereon, a treadle-operated connection, means operated by a partial movement of said connection in one direction to clutch said shaft to said pulley whereby the shaft will rotate at full speed and upon a further movement of said connection in the same direction to bring about a reduction in the speed of rotation of the shaft.

4. In a driving and stopping mechanism, the combination with a shaft, of a driving pulley thereon, automatically-operative means to clutch said pulley to said shaft, a rock shaft carrying a cam element for disengaging said clutch, a treadle-actuated member, a disk connected thereto, a slide bar, means to actuate the slide bar by rotation of the disk, and a second disk 26 connected to said slide bar and by which said rock-shaft is controlled.

5. In a driving and stopping mechanism, the combination with a shaft, of a driving pulley loosely mounted thereon, two slide bars, a treadle-operated connection, means for connecting said connection to said slide bars alternately. on successive movements of the connection, means rendered operative by movement of one slide bar to clutch the driving pulley to the shaft, means operated by the other slide bar to cause the pulley to reverse in direction and bring it to rest but at a predetermined point.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MARK THOMAS DENNE.

Witnesses:

A. E. WILLIAMs, M. POLLON.

Copies of this patent may be obtained for five cents each, by addressing the commissioner of Patents,

Washington, D. C. 

